A histological investigation of Oriental beech wood decayed by Pleurotus ostreatus and Trametes versicolor

Abstract

Chemical, light and electron microscopic studies were carried out on wood of Oriental beech (Fagus orientalis Lipsky) decayed by the white-rot fungi Pleurotus ostreatus and Trametes versicolor for 30, 60 and 120 days according to the modified European standard EN 113. Mass loss as well as lignin, cellulose and carbohydrate content were determined before and after fungal attack. There were no significant differences of wood mass loss and chemical composition between both fungi at the end of incubation. After each incubation period, small specimens were stained for microscopic studies. The micromorphology of fungal cell wall degradation was rather similar for both fungi. Both decreased the cell wall thickness to the same extent. The accumulation of hyphae as well as the rupture of cell walls was also similar. The occurrence of hyphae, cavities in the pits and vessel walls followed nearly the same patterns. The parenchyma cells were completely destroyed. Altogether, both fungi produced a simultaneous white rot in Oriental beech wood.

Chemical Composition and Antioxidant Activity of Extract from the Wood of Fagus orientalis: Water Resistance and Decay Resistance against Trametes versicolor

“…As high nitrogen concentrations stimulate polysaccharide breakdown, low nitrogen levels could promote selective lignin removal (Fenn and Kirk 1981;Reid 1983). In the present study and the study of Bari et al (2015b), the conditions of growth media were favorable for a simultaneous white rot and for the formation of bore holes and can thus be considered. Figure 2 shows the water absorption of extracted wood with different combinations of solvents.…”

“…Goktas et al (2010) found that beech wood specimens had weight losses ranging between 12.00% and 30.29% as affected by T. versicolor. The percents of the three cell wall components of Oriental beech wood (cellulose, lignin, and hemicellulose) were decreased by T. versicolor (Bari et al 2015b).…”

“…Subsequently, one of the most limiting factors for the commercial utilization of beech wood is its low resistance to fungi, especially in the semi-arid and sub-humid tropics (Istek et al 2005). Bari et al (2015b) found that T. versicolor completely destroyed the parenchyma cells and produced white rot in Oriental beech wood.…”

“…Bari et al (2015b) reported that there were no significant differences in wood mass loss and chemical composition between wood affected by Pleurotus ostreatus and T. versicolor at the end of incubation periods (30, 60, and 120 days). After each incubation period, the cell wall thickness decreased to the same extent.…”

Comparison between degradation capabilities of the white rot fungi Pleurotus ostreatus and Trametes versicolor in beech wood

“…The sections were stained using a mixture of Safranin 0.5% and Astrablue 0.3% in 1:1 ratio (Mohebby, 2003;Schweingruber et al, 2011;Bari et al, 2015). The stained samples were washed with distilled water for 1e3 min, dehydrated with a 95% and absolute ethanol series for 2e3 min.…”